WASHINGTON — The Democratic National Committee officially announced Thursday the 10 presidential candidates who qualified for a spot on the debate stage in September, the first in which former Vice President Joe Biden and Sen. Elizabeth Warren will appear together.

The other 10 candidates still in the race, many of whom participated in the first two Democratic debates, did not meet the more stringent requirements intended to winnow down the participants.

The other eight who will appear onstage in Houston with Biden and Warren, D-Mass., are Sen. Cory Booker, D-N.J.; South Bend, Indiana, Mayor Pete Buttigieg; former Health and Urban Development secretary Julián Castro; Sen. Kamala Harris, D-Calif.; Sen. Amy Klobuchar, D-Minn.); former Texas congressman Beto O’Rourke; Sen. Bernie Sanders, I-Vt.; and tech entrepreneur Andrew Yang.

The stricter criteria spurred several candidates who didn’t make the cut to drop out of the race, including Sen. Kirsten Gillibrand, D-N.Y., who ended her campaign Wednesday evening.

Among those who won’t be appearing but met some of the requirements are author Marianne Williamson, Rep. Tulsi Gabbard, D-Hawaii, and billionaire executive Tom Steyer. The rest of the candidates met none of the qualifications.

To make it on the September debate stage, each candidate needed at least 2 percent in four or more approved polls and 130,000 donors from at least 20 states. There needed to be at least 400 donors per state.

The shrinking of the debate stage marks the beginning of a two-tier nominating process, with some candidates getting prime-time national exposure and others left to gut it out in the early nominating states.

Rep. Tim Ryan, D-Ohio, one of the hopefuls who fell short of securing a spot on stage, vowed to continue his campaign.

“Obviously you want on, but we’re moving forward,” Ryan said during an interview on MSNBC. “This is not going to stop us at all.”

Ryan said that he has been well-received in Iowa, New Hampshire and other early nominating states and that there is plenty of time to win over voters.

“I’m doing it the old-fashioned way. We’re on the ground,” he said. “This race is just starting, not ending.”

Gabbard, meanwhile, took to Twitter on Thursday morning to share a clip from an interview on Fox News the night before in which she argued that the DNC debate criteria were not “transparent.”

“No transparency = no trust,” Gabbard wrote. “With your help, we will carry our message forward until we finally have a government that stands for the people, for our planet, and for peace. Stand with me.”

Candidates can continue to campaign for inclusion in the October debates, when the qualification rules will be the same.

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